title: Temporal trends in prevalence of bacteria isolated from foals with sepsis: 1979-2010.
abstract: BACKGROUND
  Sepsis is an important cause of death in foals. Knowledge of which pathogens are likely to be involved is important for selection of antimicrobial drugs for initial treatment.
  
  
  OBJECTIVE
  To identify temporal trends in prevalence of bacteria isolated from foals with sepsis between 1979 and 2010.
  
  
  METHODS
  Retrospective review of medical records.
  
  
  METHODS
  All foals ≤30 days of age presented to the Veterinary Medical Teaching Hospital (VMTH) at the University of California, Davis between 1979 and 2010, with a diagnosis of sepsis confirmed by culture of bacteria from blood or internal organs (antemortem or at necropsy), were included in the study. Conventional microbiological methods were used to identify isolated organisms. The Cochran-Armitage trend test was used for statistical analysis.
  
  
  RESULTS
  The percentage of Gram-positive isolates increased significantly over the years. The percentage Enterobacteriacea, and Klebsiella spp. in particular, decreased over time. Enterococcus spp. isolates were cultured more often in recent years.
  
  
  CONCLUSIONS
  Whereas Gram-negative bacteria, particularly Enterobacteriaceae, remain the most common isolates from neonatal foals with sepsis, the prevalence of Gram-positive bacteria is increasing. This trend underlines the importance of including antimicrobial drugs active against both Gram-positive and Gram-negative bacteria in treatment protocols while awaiting the results of bacteriological culture and susceptibility tests. The increased prevalence of Enterococcus spp. is of concern because antimicrobial susceptibility patterns for enterococci are unpredictable and enterococci can also act as donors of antimicrobial resistance genes to other bacteria.
authors.affiliation: Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
authors.forename: M J P
authors.initials: MJ
authors.lastname: Theelen
authors.forename: W D
authors.initials: WD
authors.lastname: Wilson
authors.forename: J M
authors.initials: JM
authors.lastname: Edman
authors.forename: K G
authors.initials: KG
authors.lastname: Magdesian
authors.forename: P H
authors.initials: PH
authors.lastname: Kass
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001424:Bacterial Infections / Q000382:microbiology / Q000662:veterinary*; D006734:Horse Diseases / Q000382:microbiology*; D006736:Horses; D012189:Retrospective Studies; D013997:Time Factors
keywords: Enterococcus spp.; Gram-negative bacteria; Gram-positive bacteria; horse; neonatology; sepsis